1. Chemical screening by time-resolved X-ray scattering to discover allosteric probes.
- Author
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Brosey CA, Link TM, Shen R, Moiani D, Burnett K, Hura GL, Jones DE, and Tainer JA
- Subjects
- Allosteric Regulation, Structure-Activity Relationship, X-Ray Diffraction methods, Humans, Drug Discovery methods, Models, Molecular, Kinetics, Small Molecule Libraries chemistry, Small Molecule Libraries pharmacology, Apoptosis Inducing Factor chemistry, Apoptosis Inducing Factor metabolism, Scattering, Small Angle
- Abstract
Drug discovery relies on efficient identification of small-molecule leads and their interactions with macromolecular targets. However, understanding how chemotypes impact mechanistically important conformational states often remains secondary among high-throughput discovery methods. Here, we present a conformational discovery pipeline integrating time-resolved, high-throughput small-angle X-ray scattering (TR-HT-SAXS) and classic fragment screening applied to allosteric states of the mitochondrial import oxidoreductase apoptosis-inducing factor (AIF). By monitoring oxidized and X-ray-reduced AIF states, TR-HT-SAXS leverages structure and kinetics to generate a multidimensional screening dataset that identifies fragment chemotypes allosterically stimulating AIF dimerization. Fragment-induced dimerization rates, quantified with time-resolved SAXS similarity analysis (k
VR ), capture structure-activity relationships (SAR) across the top-ranked 4-aminoquinoline chemotype. Crystallized AIF-aminoquinoline complexes validate TR-SAXS-guided SAR, supporting this conformational chemotype for optimization. AIF-aminoquinoline structures and mutational analysis reveal active site F482 as an underappreciated allosteric stabilizer of AIF dimerization. This conformational discovery pipeline illustrates TR-HT-SAXS as an effective technology for targeting chemical leads to important macromolecular states., (© 2024. The Author(s).)- Published
- 2024
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